Jan. 10: Unusual Volume Leaders

Here's a look at stocks in the S&P 1,500 index that displayed unusual volume in Tuesday's trading session.

S&P 500: Trading volume in Tiffany was up 830 percent over its 10-day average, after the jewelry retailer said Tuesday its sales growth softened in the United States during the holiday season.

S&P MidCap 400: Health Management Associates volume jumped 1,690 percent over its 10-day average, after its general counsel, Tim Parry, resigned. The company is currently being questioned over its Medicare practices.

S&P SmallCap 600: Hi Tech Pharmacal volume rose 1,100 percent over its 10-day average, as its Indian rival Wockhardt said it received FDA approval on its Fluticasone nasal spray.